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Aims Purification and characterization of a novel bacteriocin produced by strain Enterococcus faecium D081821. Methods and Results Enterococcus faecium D081821, isolated from the traditional Taiwanese fermented food dochi (fermented black beans), was previously found to produce a bacteriocin against Listeria monocytogenes and some Gram-positive bacteria. This bacteriocin, termed enterocin TW21, was purified from culture supernatant by ammonium sulfate precipitation, Sep- Pak C18 cartridge, ion-exchange and gel filtration chromatography. Mass spectrometry analysis showed the mass of the peptide to be approximately 5300·6 Da. The N-terminal amino acid sequencing yielded a partial sequence NH2- ATYYGNGVYx NTQK by Edman degradation, and it contains the consensus class IIa bacteriocin motif YGNGV in the N-terminal region. The open reading frame ( ORF) encoding the bacteriocin was identified from the draft genome sequence of Enterococcus faecium D081821, and sequence analysis of this peptide indicated that enterocin TW21 is a novel bacteriocin. Conclusions Enterococcus faecium D081821 produced a bacteriocin named enterocin TW21, the molecular weight and amino acid sequence both revealed it to be a novel bacteriocin. Significant and Impact of Study A new member of class IIa bacteriocin was identified. This bacteriocin shows great inhibitory ability against L. monocytogenes and could be applied as a natural food preservative. [ABSTRACT FROM AUTHOR]

Aim To identify and characterize novel bacteriocins from Weissella hellenica 4-7. Methods and Results Weissella hellenica 4-7, isolated from the traditional Taiwanese fermented food sian-sianzih (fermented clams), was previously found to produce a bacteriocin active against Listeria monocytogenes and some other Gram-positive bacteria. Bacteriocin activity decreased slightly after autoclaving (121°C for 15 min), but was inactivated by protease K and trypsin. Mass spectrometry analysis revealed the bacteriocin mass to be approximately 3205·6 Da. N-terminal amino acid sequencing yielded a partial sequence, NH2- KGFLSWASKATSWLVGP, by Edman degradation. The obtained partial sequence showed high homology with leucocin B- TA33a; however, at least two different residues were observed. No identical peptide or protein was found, and this peptide was therefore considered to be a novel bacteriocin produced by W. hellenica 4-7 and termed weissellicin L. Conclusions The findings obtained in the current study suggest a novel bacteriocin produced by W. hellenica 4-7. Significance and Impact of the Study Bacteriocins from Weissella remain rare, and this study is the second report of a bacteriocin produced by W. hellenica. [ABSTRACT FROM AUTHOR]

Aims To isolate, characterize and identify lactic acid bacteria ( LAB) in yan-tsai-shin (fermented broccoli stems), a traditional fermented food in Taiwan. Methods and Results A total of 226 LAB were isolated; 111 cultures were isolated from samples collected from seven different markets and 115 from six fresh broccoli samples. These isolates were characterized phenotypically and then initially divided into nine groups (r1 to r9) using restriction fragment length polymorphism analysis and sequencing of 16S ribosomal DNA. Some isolates were further divided into four additional groups by other genetic analysis. The most common bacterial genera in yan-tsai-shin and fresh broccoli were Weissella, Lactococcus and Lactobacillus. Regional similarities in the LAB, with differences in diversity, were observed in this study. On the basis of phylogenetic analysis of 16S rRNA, rpoA, rpoB and pheS gene sequences, two strains were included in the genera Enterococcus and Lactococcus, respectively, and identified as potential novel species or subspecies. In addition, the novel enterococcal strain, and 33 L. lactis subsp. lactis and two Weissella cibaria strains were found to have bacteriocin-like inhibitory substance (BLIS) producing abilities. Conclusions These results suggest that the LAB play important roles in the fermentation of yan-tsai-shin. Significance and Impact of the Study This is the first report describing the distribution and varieties of LAB existing in yan-tsai-shin and fresh broccoli. In addition, two potential novel LAB species or subspecies and one potential novel BLIS were also found in this study. [ABSTRACT FROM AUTHOR]

Aim To isolate and characterize bacteriocin-like inhibitory substance ( BLIS)-producing lactic acid bacteria from the intestine of grey mullet. Methods and Results Inhibitory activity against at least one or more indicator strains was observed in one Enterococcus thailandicus, one Enterococcus faecium and two Lactococcus garvieae strains. Enterococcus faecium B3-8 and Ent. thailandicus B3-22 showed the greatest inhibitory activities against Listeria monocytogenes ATCC 19111 and were therefore further characterized. The results suggested that the inhibitory substances from the two strains showed similar characteristics with respect to sensitivity to heat and proteolytic enzymes. BLIS from Ent. thailandicus B3-22 was characterized by a broader inhibitory spectrum than that from Ent. faecium B3-8. SDS- PAGE revealed that the molecular size of partially purified BLISs from Ent. faecium B3-8 and Ent. thailandicus B3-22 was c. 5 and 3 kDa, respectively. The molecular mass of purified bacteriocin from Ent. thailandicus B3-22 was further determined to be 6319 Da by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry ( MALDI- TOF MS). The results indicated that BLIS from Ent. thailandicus B3-22 can effectively inhibit the growth of all tested L. garvieae strains. Conclusions The findings obtained in this study suggest the potential use of Ent. thailandicus B3-22 as a biocontrol agent against pathogenic L. garvieae in the aquaculture. Significance and Impact of the Study This is the first report describing the characteristics of BLIS from Ent. thailandicus that showed potential for use as a biocontrol agent in the aquaculture. [ABSTRACT FROM AUTHOR]

SUMMARY Radiotherapy is a useful component of treatment strategies for esophageal cancer. The role of autophagy in response to ionizing radiation was investigated in human esophageal squamous carcinoma cells. Cell viability and clonogenic survival assay were used to evaluate the radiosensitivity of autophagy inhibitor (3-MA) on esophageal squamous carcinoma cells. The percentage of apoptotic cells and cell cycle analysis were assessed by flow cytometry; DAPI staining was used to detect apoptotic cells. The expression of beclin-1 and LC3 was measured using a Western blot. The ultrastructural analysis was under the electron microscope. 6 Gy irradiation induced a massive accumulation of autophagosomes accompanied by strong upregulation of beclin-1 and LC3-II expression in TE-1 cells. Compared with radiation alone, 3-MA combined with radiation significantly decreased cell viability, as well as autophagic ratio, beclin-1, and LC3-II protein level. Inhibition of autophagy increased radiation-induced apoptosis and the percentage of G2/M-phase cells. Blockade of autophagy with 3-MA enhanced cytotoxicity of radiotherapy in human esophageal squamous carcinoma cells. It suggests that inhibition of autophagy could be used as adjuvant therapy to treat esophageal squamous cell carcinoma. [ABSTRACT FROM AUTHOR]

Aims: To characterize bacteriocin-like inhibitory substances (BLIS) from two dochi-isolated Enterococcus faecium. Methods and Results: Enterococcus faecium D081821 and D081833 were isolated from dochi (a traditional fermented food in Taiwan) and found to produce BLIS with inhibitory activities against Listeria monocytogenes, Clostridium perfringens, and Bacillus cereus. Strains D081821 and D081833 showed different growth temperatures and their BLIS showed different sensitivities to heat, proteolytic enzymes, and antibacterial spectra. Both BLIS were collected, partially purified, and analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). SDS-PAGE showed that both partially purified BLIS were approximately 3·0 kDa in size. Conclusions: These results indicate that E. faecium D081821 and D081833 produce different BLIS with strong antibacterial actions against the tested pathogenic bacteria. Significance and Impact of the Study: The results of this study suggest that two different BLIS from dochi-isolated lactic acid bacteria have potential for use as food preservatives. [ABSTRACT FROM AUTHOR]

Aims: To isolate, characterize and identify lactic acid bacteria (LAB) in dochi (fermented black beans), a traditional fermented food in Taiwan. Methods and Results: A total of 30 samples were collected from three different dochi producers and analysed after different periods of storage. Fifty-two cultures of LAB were isolated from dochi samples and the isolates were divided into classes by phenotype and then into groups by restriction fragment length polymorphism analysis and sequencing of 16S ribosomal DNA. Phenotypic and biochemical characteristics identified six different bacterial groups (A–F) and showed that the majority of the isolates were homofermentative LAB. Enterococcus faecium was the most abundant of the dochi-isolated LAB. All isolated LAB were able to grow in MRS broth containing 6% NaCl, but only Enterococcus, Pediococcus and Tetragenococcus species could grow in MRS broth containing 10% NaCl. Furthermore, antibacterial activities of isolates were determined, and four isolates showed inhibitory activities against the indicator strain Lactobacillus sakei JCM 1157T. Conclusions: These results suggest that Ent. faecium is the main LAB present during the fermentation of dochi. Significance and Impact of the Study: This is the first report describing the distribution and varieties of LAB that exist in the dochi fermentation process. [ABSTRACT FROM AUTHOR]

Aims: To isolate, characterize, and identify lactic acid bacteria (LAB) in suan-tsai (fermented mustard), a traditional fermented food in Taiwan. Methods and Results: Suan-tsai samples were collected at five time points from a fixed fermenting bucket. Fifty cultures were isolated from suan-tsai samples, and isolates were divided into classes by phenotype and then into groups by restriction-fragment length polymorphism analysis and sequencing of 16S ribosomal DNA. Phenotypic and biochemical characteristics identified two different bacterial groups (A and B), and the results showed that Pediococcus pentosaceus was the most abundant LAB during the initial fermentation time. However, the more NaCl-tolerant species Tetragenococcus halophilus took the place of P. pentosaceus and became the most abundant LAB later. All isolates were grown in de Man, Rogosa, and Sharpe (MRS) broth containing 6% NaCl, but T. halophilus could grow only in MRS broth containing 10% NaCl. Conclusions: These results suggest that the LAB P. pentosaceus and T. halophilus play roles in the fermentation of suan-tsai. Significance and Impact of the Study: This is the first report describing the distribution and varieties of LAB that exist in the suan-tsai fermentation process. [ABSTRACT FROM AUTHOR]

y.-s. chen, f. yanagida and t. shinohara. 2005.To survey, and identify and classify the ecological distribution of lactic acid bacteria from soil in Japan and Taiwan.Acid-producing bacteria were isolated from 68 soil samples, collected from Japan and Taiwan, in the rhizospheres of fruit trees, from the floor of a henhouse and around a horse farm. All isolates were identified by physiological and genetic tests. Thirty-two of the 54 isolates were identified as lactic acid bacteria (LAB), 16 as spore-forming lactic acid bacteria, five asClostridiumand one asBacillus. These lactic acid bacteria represent five genera:Lactobacillus,Lactococcus,Enterococcus,LeuconostocandWeissella.A high rate of isolating lactic acid bacteria was obtained from soil.This study suggests that soil may be a common source for the isolation of lactic acid bacteria. [ABSTRACT FROM AUTHOR]

y.-s. chen and j.l. steele. 2004.To clone and analyse seven putative promoter fragments (pepC,pepN,pepX,pepO,pepE,pepO2,hsp17) fromLactobacillus helveticusCNRZ32 for their expression inLact. helveticusCNRZ32,Lact. caseiATCC334 andLactococcus lactisMG1363.Promoter fragments were fused to the promoter-lessβ-glucuronidase (gusA) gene on pNZ272 RBS− ATG−. The resulting constructs were evaluated for their ability to drive the expression of active GusA with 0·5 mmol l−1 5-bromo-4-chloro-3-indolyl-β-d-glucuronide. All promoters exceptP pepN::gusAwere active in the examined strains. Northern hybridization was performed to examine the promoter strength. Sequence analysis of these promoters identified well conserved putative ribosomal binding and putative–10 hexamers sites.Seven promoter fragments fromLact. helveticusCNRZ32 were recognized in the lactic acid bacteria,Lact. caseiATCC334 andL. lactisMG1363, as well as inEscherichia coli.P pepN::gusAcould not be maintained in the strains examined because of toxicity associated with heterologous protein over-expression driven byP pepN.This study revealed that desirable levels of heterologous food-grade protein production in GRAS organisms can be obtained with the application of natural promoter fragments from closely related organisms. [ABSTRACT FROM AUTHOR]

Cytidine deaminase activity (CD) in the neutrophil culture supernatants (PMN SUP) of 27 patients with systemic lupus erythematosus (SLE) was measured using a spectrophotometric method. Compared with the controls (5.449±1.358 U/5 × 10 PMN), the CD activity in the spontaneous culture supernatants of PMN was significantly increased in active (10.003±2.637 U/5 × 10 PMN) but not in inactive (5.358±1.624 U/5 × 10 PMN) SLE. However, after stimulation with -formyl-methionyl-leucyl-phenylalanine (FMLP, 1 × 10 M), the ratio of enzyme activity between stimulated and spontaneous PMN supernatants was decreased in active SLE (0.794±0.178) compared with normal controls (1.300±0.225). In contrast, the enzyme activity in the cytoplasm of either stimulated or non-stimulated PMN was not different among these three groups. These results suggest that CD of PMN is releasable and can be enhanced by chemotactic factor stimulation in normal PMN. The increased spontaneous release of CD by active SLE PMN is one of the indicators for the disease activity in these patients. [ABSTRACT FROM PUBLISHER]

The article presents a case study of a 33-year-old homosexual man who was diagnosed with HIV infection. The patient was presented with a tender mass on the right neck after the secondary prophylaxis for Cryptococcus neoformans was discontinued. It says that lymphadenitis in HIV-infected patients was caused by Cryptococcus infection-related immune reconstitutional inflammatory syndrome (IRIS). It adds that the mass disappeared after oral prednisolone and fluconazole treatments.